About 100 employees and contractors working for Sherritt are at the site trying to determine how a wall in the containment pond was breached, propelling a plume of clay, coal dust, dirt, sandstone and shale through two creeks and into the Athabasca River. The company couldn’t say Monday when the walls were last inspected.

Calling the leak “huge,” Notley asked why it took five days for Alberta Environment to warn communities to stop drawing water from the river. She said officials in British Columbia issued immediate warnings in August when 65,000 litres leached from a coal tailings pond into the Tulameen River.

“I think government’s response is more proof that it can’t be trusted to act in the public’s best interest,” Notley said. “When this occurred in B.C., government reassured people everything was fine­ — but immediately told them not to drink the water or go into it.

“Why, with a billion-litre spill, was there a delay here? This is gargantuan, and these are not organic compounds. Coal waste includes a number of toxic compounds. (Government’s) handling of this is grossly irresponsible.”

Communities downstream have been warned to use caution, although most draw drinking water from wells and not the river itself. Only the city of Fort McMurray, town of Athabasca and hamlet of Smith, in the municipal district of Lesser Slave Lake, draw directly from the river.

Mayor Roger Morrill of Athabasca said the town shut off its water supply from the river on Friday, and will rely on reserves. Pollutants drifting slowly with the current are not supposed to reach Athabasca, about 170 kilometres east of the spill site, until Wednesday. Fort McMurray is so far distant that it could be at least next week before the plume reaches there.

Much farther east, the Alberta Newsprint Company’s mill in Whitecourt, the only paper mill in Alberta, was shut down by the spill over the weekend, but was back in operation early Monday.

“It’s just one of those things,” Woodlands County Mayor Jim Rennie said. “It’s unfortunate, but I think it is being handled as best as it can be.”

The Alberta Energy Regulator said Monday no similar incidents involving coal mine containment facilities has occurred within the past five years in the province. There are four coal processing plants in Alberta, with seven containment and recycling facilities.

Mines are inspected once a year, or more frequently if concerns are identified, the regulator said. The department did not say when the last inspection occurred.

Wildrose critic Joe Anglin blasted government and industry, and called such incidents preventable.

“What’s happening is inexcusable,” Anglin said. “We are seeing a real negative trend when it comes to train derailments and leaks, whether from pipelines or containment facilities. It shouldn’t happen if there is regular maintenance and monitoring.

“The company will take the blame, but where was the government oversight? This thing didn’t just break overnight. We should have seen it coming.”

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